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Analytical Techniques in Uranium Exploration and Ore Processing

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Analytical Techniques in Uranium Exploration and Ore Processing TECHNICAL REPORTS SERIES No 341 vv*« * ^ % /3>i Analytical Techniques in Uranium Exploration and Ore Processing (#}9 INTERNATIONAL ATOMIC ENERGY AGENCY, VIENNA, 1992 ANALYTICAL TECHNIQUES IN URANIUM EXPLORATION AND ORE PROCESSING The following States are Members of the International Atomic Energy Agency: AFGHANISTAN HOLY SEE PANAMA ALBANIA HUNGARY PARAGUAY ALGERIA ICELAND PERU ARGENTINA INDIA PHILIPPINES AUSTRALIA INDONESIA POLAND AUSTRIA IRAN, ISLAMIC REPUBLIC OF PORTUGAL BANGLADESH IRAQ QATAR BELARUS IRELAND ROMANIA BELGIUM ISRAEL RUSSIAN FEDERATION BOLIVIA ITALY SAUDI ARABIA BRAZIL JAMAICA. SENEGAL BULGARIA JAPAN SIERRA LEONE CAMBODIA JORDAN SINGAPORE CAMEROON KENYA SLOVENIA CANADA KOREA, REPUBLIC OF SOUTH AFRICA CHILE KUWAIT SPAIN CHINA LEBANON SRI LANKA COLOMBIA LIBERIA SUDAN COSTA RICA LIBYAN ARAB JAMAHIRIYA SWEDEN COTE D'lVOIRE LIECHTENSTEIN SWITZERLAND CUBA LUXEMBOURG SYRIAN ARAB REPUBLIC CYPRUS MADAGASCAR THAILAND CZECHOSLOVAKIA MALAYSIA TUNISIA DEMOCRATIC PEOPLE'S MALI TURKEY REPUBLIC OF KOREA MAURITIUS UGANDA DENMARK MEXICO UKRAINE DOMINICAN REPUBLIC MONACO UNITED ARAB EMIRATES ECUADOR MONGOLIA UNITED KINGDOM OF GREAT EGYPT MOROCCO BRITAIN AND NORTHERN EL SALVADOR MYANMAR IRELAND ESTONIA NAMIBIA UNITED REPUBLIC OF ETHIOPIA NETHERLANDS TANZANIA FINLAND NEW ZEALAND UNITED STATES OF AMERICA FRANCE NICARAGUA URUGUAY GABON NIGER VENEZUELA GERMANY NIGERIA VIET NAM GHANA NORWAY YUGOSLAVIA GREECE PAKISTAN ZAIRE GUATEMALA ZAMBIA HAITI ZIMBABWE The Agency's Statute was approved on 23 October 1956 by the Conference on the Statute of the IAEA held at United Nations Headquarters, New York; it entered into force on 29 July 1957. The Head­ quarters of the Agency are situated in Vienna. Its principal objective is "to accelerate and enlarge the contribution of atomic energy to peace, health and prosperity throughout the world". © IAEA, 1992 Permission to reproduce or translate the information contained in this publication may be obtained by writing to the International Atomic Energy Agency, Wagramerstrasse 5, P.O. Box 100, A-1400 Vienna, Austria. Printed by the IAEA in Austria December 1992 TECHNICAL REPORTS SERIES No. 341 ANALYTICAL TECHNIQUES IN URANIUM EXPLORATION AND ORE PROCESSING INTERNATIONAL ATOMIC ENERGY AGENCY VIENNA, 1992 VIC Library Cataloguing in Publication Data Analytical techniques in uranium exploration and ore processing. — Vienna : International Atomic Energy Agency, 1992. p. ; 24 cm. — (Technical reports series, ISSN 0074-1914 ; 341) STI/DOC/10/341 ISBN 92-0-103792-9 Includes bibliographical references. 1. Uranium ores—Analysis. 2. Chemistry, Analytic—Technique. I. International Atomic Energy Agency. II. Series: Technical reports series (International Atomic Energy Agency) ; 341. VICL 92-00048 FOREWORD The Manual was prepared as part of a programme of the International Atomic Energy Agency to publish instruction manuals on a wide range of practical topics. Its purpose is to assist in the establishment of an analytical laboratory able to perform all the basic chemical and instrumental analyses commonly used in conjunction with uranium exploration and mining and ore processing activities, including the develop­ ment of hydrometallurgical processes. It is intended for chemists with a general background in analytical chemistry, but with limited experience in the analytical chemistry of uranium and of related elements. The Manual is divided in two parts. The first deals with the general aspects of laboratory design and operation and the second contains descriptions of 17 selected analytical methods that have generally been accepted in the international uranium industry. Other methods which may produce comparable results using more sophisticated, modern or efficient techniques have not been included, but are referred to in the general references. Also not included are those analytical methods which are widely used in the chemical industry and which may be found in readily available analytical chemistry manuals. The Manual is based, in part, on techniques developed throughout the analyti­ cal community worldwide and, in particular, in the Grand Junction Laboratory of the United States Department of Energy (Grand Junction, Colorado) and at the Canada Centre for Mineral and Energy Technology (Ottawa, Ontario). The Agency wishes to thank the Consultants who took part in the preparation of the Manual. They included R. Chessmore, United States Department of Energy, Grand Junction, Colorado, USA; J.L. Dalton, Canada Centre for Mineral and Energy Technology (CANMET), Energy Mines and Resources Canada, Ottawa, Ontario, Canada; and O. Suschny (retired), former head of the Analytical Chemistry Section of the IAEA Laboratory at Seibersdorf, Austria. Their valuable contribu­ tions, and those of their colleagues and associates, form the substance of the Manual. The Agency staff members responsible for the project were S. Ajuria and A. Y. Smith of the Division of Nuclear Fuel Cycle and Waste Management. EDITORIAL NOTE The Manual has been edited by the editorial staff of the IAEA to the extent considered necessary for the reader's assistance. The views expressed remain, however, the responsibility of the named contributors. In addition, the views are not necessarily those of the governments of the nominating Member States or of the nominating organizations. The use of particular designations of countries or territories does not imply any judge­ ment by the publisher, the IAEA, as to the legal status of such countries or territories, of their authorities and institutions or of the delimitation of their boundaries. The mention of names of specific companies or products (whether or not indicated as registered) does not imply any intention to infringe proprietary rights, nor should it be construed as an endorsement or recommendation on the part of the IAEA. The contributors are responsible for having obtained the necessary permission for the IAEA to reproduce, translate or use material from sources already protected by copyrights. CONTENTS INTRODUCTION 1 PART I. GENERAL ASPECTS OF LABORATORY OPERATION CHAPTER 1. URANIUM EXPLORATION 5 1-1. Introduction 5 1-1.1. Area selection 5 1-1.2. Reconnaissance phase 6 1-1.3. Follow-up phase 6 1-1.4. Detailed phase 7 1-1.5. Deposit development 7 1-2. Analytical requirements for uranium exploration 8 CHAPTER 2. ANALYTICAL REQUIREMENTS IN URANIUM ORE PROCESSING AND PROCESS DEVELOPMENT 10 2-1. Introduction 10 2-2. Uranium extraction technology 10 2-3. Uranium extraction development projects 12 2-3.1. Order of magnitude studies 12 2-3.2. Preliminary feasibility studies 13 2-3.3. Licensing 13 2-3.4. Preliminary project evaluation 13 2-3.5. Final feasibility studies 13 2-3.6. Final evaluation and decision to invest 14 2-3.7. Detailed engineering 14 2-3.8. Startup and commissioning 14 2-4. Analytical requirements for process development and plant operation 14 2-4.1. Ores 16 2-4.2. Process water 16 2-4.3. Reagents 16 2-4.4. Process solutions 17 2-4.5. Process solids 17 2-4.6. Uranium concentrates 17 2-4.7. By-products or co-products 18 2-4.8. Tailings 18 CHAPTER 3. ANALYTICAL CHEMISTRY OF URANIUM 19 3-1. Properties of uranium compounds 19 3-2. Analytical methods for uranium 20 3-2.1. Radiometry 20 3-2.2. Neutron activation analysis 21 2-2.3. Delayed neutron counting 21 3-2.4. X ray fluorescence analysis 22 3-2.5. Fluorometry 23 3-2.6. Spectrophotometry 23 3-2.7. Gravimetry and volumetry 24 3-2.8. Other methods 25 3-3. Selection of a suitable method 26 CHAPTER 4. THE URANIUM ANALYTICAL LABORATORY 27 4-1. Introduction , 27 4-2. Laboratory organization 27 4-2.1. Laboratory responsibilities 27 4-2.2. Laboratory organization 28 4-2.3. Personnel 29 4-2.4. Operational procedures 31 4-2.5. MIS 33 4-2.6. Laboratory design and layout 33 4-2.7. Main equipment 35 CHAPTER 5. SAMPLE PREPARATION 37 5-1. Introduction 37 5-2. Sample flow 37 5-3. Laboratory facilities ; 39 5-4. Sample preparation 39 5-4.1. Rock sample preparation 39 5-4.2. Stream sediment and soil sample preparation 40 5-4.3. Vegetation sample preparation 40 5-4.4. Liquid samples 41 5-4.5. Cleaning of equipment 41 5-5. Equipment and use 41 CHAPTER 6. CALIBRATION METHODS AND QUALITY CONTROL IN THE URANIUM ANALYTICAL LABORATORY 43 CHAPTER 7. STATISTICAL TECHNIQUES FOR CHEMICAL ANALYSIS AND PROCESS CONTROL 50 7-1. Introduction 50 7-2. Frequency distribution 51 7-3. Accuracy 51 7-3.1. Precision 52 7-3.2. Trueness 53 7-4. Source of errors 53 7-4.1. Sampling . 53 7-4.2. Sample preparation 54 7-4.3. Measurement error 54 7-4.4. Overall measurement error 54 7-5. Statistical inference 55 7-6. Control charts 56 7-6.1. Mean chart 57 7-7. Range chart 57 7-7.1. Construction and update of control charts 58 7-7.2. Practical interpretation of control charts 59 REFERENCES 61 PART n. ANALYTICAL METHODS METHOD 1. ANALYTICAL PROCEDURES FOR FLUOROMETRIC DETERMINATION OF LABILE URANIUM 65 1-1. Introduction 65 1-2. Preparation of equipment and reagents 65 1-3. Weighing 66 1-4. Leaching 67 1-5. Fusion and fluorometric measurement 67 1-6. Determination of uranium in water samples , 68 1-7. Preparation of the standard graph 69 1-8. Notes 69 1-9. Equipment and reagents required for the establishment of a geochemical laboratory for fluorometric uranium analysis 70 1-9.1. Equipment 70 1-9.2. Special equipment 71 1-9.3. Reagents (sufficient for 1 year of operation) 71 Reference , 72 METHOD 2. DETERMINATION OF URANIUM IN WATER USING A SCINTREX UA-3 URANIUM ANALYSER 73 2-1. Introduction 73 2-2. Interferences 73 2-3. Precision and reporting limit 73 2-4. Reagents 74 2-5. Methods 74 2-5.1. Instrument conditions 74 2-5.2. Standards 74 2-5.3. Calibration method 74 2-5.4. Measurement method 75 2-6. Calculations 75 2-7. Notes 76 References 76 METHOD 3. DETERMINATION OF URANIUM IN GEOLOGICAL MATERIALS BY FLUOROMETRY 77 3-1.
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